Can I issue a few invoices a year in Spain without registering as self-employed (autónomo), or do I have to register, even if only for one month?

This is a very common question: there is a widespread belief that you can issue 2 or 3 invoices a year, or invoice up to €15,000, without registering as an autónomo (self-employed). No such rule exists. Anyone who invoices for an economic activity, even on a one-off basis, must meet their obligations with the Spanish Tax Agency (Hacienda). With Social Security there are some nuances.

Tax obligations: register before you invoice

Before invoicing, you must register with the Tax Agency by filing Modelo 036 or 037 (Spanish census registration form for business activities), under the IAE heading (business activity code) that matches your activity. If you register just to issue a few specific invoices, you will need to:

• Issue the invoices with IVA (Spanish VAT), generally at 21%.
• Apply the relevant IRPF withholding (income tax withheld at source) if the client is a company or a professional.
• File Modelo 303 (quarterly VAT return) and, where applicable, Modelo 130 (quarterly income tax prepayment).
• Deregister from the census once you have finished invoicing.

Registration must be done before starting the activity. If the service has already been provided and you register afterwards, when invoicing, there is a risk. It is minor, but worth bearing in mind.

Is it a problem to have few expenses?

No. Income tax (IRPF) is charged on net income, i.e. income minus deductible expenses. That net income is added to the rest of your income for the year in your annual tax return. With few expenses you will pay tax on almost everything you invoice, but that does not prevent you from registering.

Under the simplified direct assessment method (estimación directa simplificada) there is also a deduction for hard-to-justify expenses on net income, subject to an annual cap. The percentage has changed in some years, so it is worth checking it for the current year.

Social Security: registering with the RETA

The obligation to register with the RETA (Spanish special Social Security scheme for self-employed workers) depends on the activity being habitual, personal and direct (Article 305 of the General Social Security Act, LGSS).

Some Supreme Court rulings have held that there is no habitual activity when annual income does not exceed the national minimum wage. However, this is case law, not an exemption: it is not binding on the General Social Security Treasury or the Labour Inspectorate. Relying on it is risky and we do not recommend it, even though many people do.

If you register with the RETA, even for a single month, you will pay that month's contribution. If you have not been registered in the last 2 years (3 if you previously benefited from the flat rate, tarifa plana), you can apply the reduced contribution for new self-employed workers.

Be careful if you already hold an interest in a company

Before deciding, two issues need to be reviewed:

• Who the income belongs to. If the commissions or services were generated on behalf of a company, the company should be the one invoicing. Invoicing them personally to keep them out of the company can be problematic, especially if it has debts or creditors, as it could be seen as diverting income.
• Whether you should already be in the RETA. Directors of the company, or those with a significant shareholding and management duties, may be required to register as a company self-employed (autónomo societario) (Article 305.2.b LGSS). This changes the picture entirely.

Every case depends on the specific circumstances, so we recommend reviewing it with an adviser before issuing any invoices.